Role of FDG PET in the management of childhood lymphomas--case proven or is the jury still out?

Positron emission tomography (PET) is a novel non invasive functional imaging modality that is increasingly used for the primary staging of lymphomas and assessment of therapeutic response. This review evaluates the published reports of its use in childhood lymphomas, particularly in the primary staging, response assessment and monitoring after completion of treatment. Specific attention is focused on the clinical circumstances in which FDG PET is most likely to have an impact on management and some indications for its use in childhood lymphomas are suggested.

A multicenter, randomized, double-blind, controlled trial of nebulized epinephrine in infants with acute bronchiolitis.

BACKGROUND: The treatment of infants with bronchiolitis is largely supportive. The role of bronchodilators is controversial. Most studies of the use of bronchodilators have enrolled small numbers of subjects and have examined only short-term outcomes, such as clinical scores. METHODS: We conducted a randomized, double-blind, controlled trial comparing nebulized single-isomer epinephrine with placebo in 194 infants admitted to four hospitals in Queens-land, Australia, with a clinical diagnosis of bronchiolitis. Three 4-ml doses of 1 percent nebulized epinephrine or three 4-ml doses of normal saline were administered at four-hour intervals after hospital admission. Observations were made at admission and just before, 30 minutes after, and 60 minutes after each dose. The primary outcome measures were the length of the hospital stay and the time until the infant was ready for discharge. The secondary outcome measures were the degree of change in the respiratory rate, the heart rate, and the respiratory-effort score and the time that supplemental oxygen was required. RESULTS: There were no significant overall differences between the groups in the length of the hospital stay (P=0.16) or the time until the infant was ready for discharge (P=0.86). Among infants who required supplemental oxygen and intravenous fluids, the time until the infant was ready for discharge was significantly longer in the epinephrine group than in the placebo group (P=0.02). The need for supplemental oxygen at admission had the greatest influence on the score for severity of illness and strongly predicted the length of the hospital stay and the time until the infant was ready for discharge (P<0.001). There were no significant changes in the respiratory rate, blood pressure, or respiratory-effort scores from before each treatment to after each treatment. The heart rate was significantly increased after each treatment with epinephrine (P=0.02 to P<0.001). CONCLUSIONS: The use of nebulized epinephrine did not significantly reduce the length of the hospital stay or the time until the infant was ready for discharge among infants admitted to the hospital with bronchiolitis.

Gallium-68 PSMA uptake in adrenal adenoma.

Gallium-68 (Ga-68) labelled prostate-specific membrane antigen (PSMA) imaging by positron emission tomography (PET) has emerged as a promising tool for staging of prostate cancer and restaging of disease in recurrence or biochemical failure after definitive treatment of prostate cancer. Ga-68 PSMA PET produces high target-to-background images of prostate cancer and its metastases which are reflective of the significant overexpression of PSMA in these cells and greatly facilitates tumour detection. However, relatively little is known about the PSMA expression of benign neoplasms and non-prostate epithelial malignancies. This is a case report of PSMA uptake in an adrenal adenoma incidentally discovered on PET performed for restaging of biochemically suspected prostate cancer recurrence. With the increasing use of PSMA PET in the management of prostate cancer - and the not infrequent occurrence of adrenal adenomas - the appearance of low- to moderate-grade PSMA uptake in adrenal adenomas should be one with which reporting clinicians are familiar.

The 'double pituitary hot spot' sign of skull base meningioma on gallium-68-labelled somatostatin analogue PET.

Gallium-68 ((68) Ga)-labelled somatostatin analogue imaging by positron emission tomography (PET) is increasingly replacing single photon (such as (111) In-labelled octreotide) imaging in the detection and staging of carcinoid and other neuroendocrine tumours. Among other tissues, pituitary uptake of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-octreotate (DOTA-TATE) and other somatostatin analogues is physiological. DOTA-TATE also accumulates in meningiomas, which have a high density of somatostatin receptor expression. The combination of pituitary and skull base meningioma uptake results in a characteristic 'double hot spot' appearance, which indicates the presence of a meningioma. This is a case of a middle-aged woman who underwent (68) Ga-DOTA-TATE PET for confirmation and staging of clinically suspected carcinoid tumour, in whom a skull base meningioma was incidentally discovered. With the increasing use of PET in the management of neuroendocrine tumours - and the not infrequent occurrence of meningiomas - the appearance of meningiomas on somatostatin analogue imaging should be one with which reporting clinicians are familiar.